Excitation Spectrum of the Holstein Model

TL;DR

This paper investigates the excitation spectrum of the Holstein model's polaron problem in the weak coupling regime using second order perturbation theory to analyze renormalized particles.

Contribution

It introduces a method to construct and label eigenstates and excitation spectra for the Holstein model in the weak coupling limit.

Findings

Eigenstates are successfully labeled and characterized.

The excitation spectrum reveals detailed polaron features.

Perturbation theory provides accurate descriptions in the weak coupling regime.

Abstract

In this paper the polaron problem for the Holstein model is studied in the weak coupling limit. We use second order perturbation theory to construct renormalized electron and phonons. Eigenstates of the Hamiltonian are labelled and the excitation spectrum is constructed.